During the systole portion of the cardiac cycle ventricular pressure may be equal to the aortic pressure immediately prior to the opening of the aortic valve and the pumping of blood into the body from the heart. A measurement of an elevated left ventricular pressure above an average reading has diagnostic value for the health of a patient.
Left ventricular pressure and aortic pressure may be determined accurately via invasive procedures. In addition, other diagnostic values such as the left ventricular end-diastolic pressure, e.g., the pressure of blood entering the heart from the lungs may also be of value as a diagnostic tool, and may also be determined via invasive procedures, for example, via pulmonary artery catheterization through the femoral vein in the leg where the catheter may be advanced toward the heart to determine the pressure values. A non-invasive determination of left ventricular pressure may have numerous clinical applications.